Friday, May 11, 2012

As Traffic Permits (ATP) Discourages Cycling

Cyclists can ride on this five lane 50 mph (80 kph) street, as traffic permits

In "Bicycle Commuting Tips: The Myth of Blood, Sweat, and Tears," I made the case that the main doubts that people raise to me about bicycle commuting don't really hold up on examination, and the true benefits of it outweigh the costs. When I wrote that post, I really did believe that bicycle commuting is much simpler than non-cyclists believe. Just get on a bike, and ride it to work, is really all that it is needed.

While that may be true, it is not a complete or decisive picture. Not many people ride their bikes to work, one can clearly observe. About 1% in Phoenix, is the current statistic. So what's going on?

Well, I may have been accurate regarding the essential, factual nature of the mechanics of bicycle commuting, or bike riding in general, but I failed to address the perceptions underlying the objections. Perception, you see, is reality. Fail to understand the perception, and you fail to understand the reality. And I can tell you, based on dozens of conversations, whatever the mechanics of bicycle commuting are, the perception is that it is dangerous. Really, really dangerous. As in, you have to be crazy to ride out there on the streets, with all those cars. Usually, said by people who drive those cars, so they ought to know, I guess, and in any case believe that they know, because they drive all the time.

With proper training and technique, the mechanics of riding a bicycle on those streets, with all that traffic, can actually be pretty safe. I've had close calls, and I can see the basis for the concern, sure, but what's really the source of the perception? What's actually going on? And how could I be basically right about the mechanics of bicycle commuting, yet so far off the mark when it comes to the perception of it?

In one of my favorite posts, "The Fruit of Error," I made the point that the source of advances in understanding is often mistakes which are understood as such, analyzed, and evaluated. My mistaken understanding of bicycle commuting, based on a lack of appreciation for the common perception of it as dangerous, led me to ponder, for a long time, on many, many rides on these busy streets, if there is a core, or underlying, concept which actually supports the perception. Is there a common principle at work which actually agrees with, or supports, or nurtures, the perception that bike riding on streets like these is dangerous?

To boil it down to its most basic form: if you get on your bike and ride, what's the first problem you run into which supports the perception that it's a crazy dangerous idea?

I found the answer in an innocuous-sounding phrase in the book "Effective Cycling." This post is not about that book, nor is the concept a key or core theme in the book, even though it possibly should be, because for me, it represents the entire program. The little phrase embraces the present reality of cycling in America in three simple words: As Traffic Permits (ATP).

At first, you notice ATP when it's time to merge, or turn, or cross, or take the lane, or enter or leave a bike lane, and then eventually you come to realize that when there's traffic, which can be most or all of the time when you're commuting by bicycle, more or less everything you do is ATP.

In my experience, a lot of my own successful and even fun bicycle commuting involves communication with hand signals, lane position, predictable and legal movement, patience, etc, and gaining the "permits" in ATP can be a two-way dialogue. I get it, and it can mechanically work, and I generally feel safe doing it, although much less so on the busy, fast street in the photo. But again, this is not about the mechanics of it working, or how I feel about it after several years of practice, but rather the root of the perception. Imagining a novice rider coming up to the stop sign on an entering side street here, on 44th Street in Phoenix, at rush hour, I'll tell you the root of the perception that it is a crazy dangerous place to ride a bicycle: As Traffic Permits. ATP.

When the cyclist approaches the stop sign, they instinctively realize that to cross this street, or to turn and merge onto it, or to do pretty much anything related to moving on or over it on the bicycle, all of it is ATP. Mechanically it can be done, of course, but the perception is that it requires Traffic to Permit the action. Sometimes this just means a gap of sufficient size opening, while other times it involves actual permitting by a driver, to yield. In any of these cases, however, there is one very accurate and key truth about the perception of of the danger of ATP: get it right and it mechanically works, but get it wrong, in any way, and at 50 mph it ends very badly, very quickly.

At 50 mph, a moving object covers 73 feet per second (or, at 80 kph it covers 22 m/s for you metrics out there). Which immediately indicates the central, fatal flaw with ATP: if any of the key parts of ATP are misjudged or misaligned, the speeds involved mean the mistake is potentially fatal very quickly. If the "As" part, the timing, is misjudged, if the "Traffic" part, the sum of the vehicles moving on the road and the gaps between them, is not accurately and instantly assessed and converted into an effective moving mental map, if the "Permits" part, the gap or ability for the bicycle to make the desired move is poorly judged, death is very possible and only a moment away, and our perception grasps this reality without hesitation. The margin for disaster or death is a split-second, in the ATP world. If it takes five seconds to assess the current traffic state, decide if Traffic Permits, and cross, the assessment needs to take into account five lanes of traffic at a distance of almost 400 feet in both directions. That's intense, and daunting, however you look at it.

ATP, As Traffic Permits, is in effect wherever cars and bicycles (and pedestrians for that matter) mix. It is particularly in effect where there are bike lanes, a reality which is seldom explicitly understood, even while the perception of danger is still present. ATP includes the scenario of vehicles crossing the painted line, which they sometimes do with terrible results, as happened with the death of 53-year-old Shawn McCarty at 4:30 on a recent sunny afternoon in Scottsdale. Traffic did not permit, and he had little or no chance of knowing, and little or no time to react. But more generally, ATP comes into play in bike lanes wherever motor vehicles and bicycles mix through entering, leaving, crossing, turning, merging or diverging, all of which are common and necessary maneuvers on our current streets, with or without bike lanes, in fact. And all of them ending up having ATP at their center. To complete the maneuver safely and successfully, an accurate split-second ATP calculation must be made by the cyclist certainly, and often by the involved motorists as well.

The only successful alternative I have seen to ATP are the comprehensive and holistic cycling infrastructure and laws such as those enacted in the Netherlands, and Denmark, for example. ATP is not the way to go, if you want or need more than 1% of your citizens to cycle to work, or if more people want to cycle, but are stifled by the perception that it is crazy dangerous to do so on the streets we currently have. ATP is bull.

The reality of ATP: traffic does not permit. It fills up the space available to it, and moves as fast as it can.

Motor vehicle traffic consumes all the space that is opened to it, clogs it up, and travels it as quickly as possible. It does not permit. It excludes. ATP nurtures in the mind of potential cyclists the not-wrong perception that it is crazy dangerous to venture out into it on a bicycle. Yes it is economically easy to obtain a working bicycle. Yes it is quite simple to get on it, and ride it to work. All true. But not the full story. The full story takes into account the strong, engrained perception that ATP is bull feces, from a safety assurance perspective. Ultimately, this is a perception of motorists, by motorists, who know what they know. And they know that it is crazy to trust in ATP, to rely on split-second decisions, to place your life into the hands of their distracted texting and tweeting kind.

This has led me to the realization that true separated infrastructure, a physically separate system of bicycle roads, bridges, tunnels, and signals, along with laws and practices which enforce strict motorist liability along with vulnerable user recognition, is the way to go. True Cycling Support (TCS) is what is needed to address the perception of crazy road danger and nurture the key perception of subjective safety, not ATP.

Any program, any technique or cycling methodology, any road feature or new paint, any enhancement or project which relies on ATP, actually ensures that more people will not cycle, as it perpetuates the problem by perpetuating the perception that the streets are dangerous places for cyclists.

One of the greatest aspects of cycling is that it can be a cheap, simple way to enjoy and experience the freedom of movement, of travel, of exploration, and discovery. In fact, and as I said in my Blood/Sweat/Tears myth post, the actual mechanical and economic barriers to get on a bicycle and go for a ride are trivial. However, the first, the and greatest, barrier that one will encounter that will interfere with that freedom and undermine that simplicity is ATP. The rub is, ATP is generally not intended to be that barrier. Right? It's meant to be, and is, a guideline for using the car-choked roads we have.

Intended or not, though, ATP is the first and most significant barrier to achieving the sense of subjective safety required to overcome the perception that cycling on those roads is crazy dangerous, the engrained perception which stands between potential cyclists and the freedom to move around and explore their own world on their own terms under their own power. So intentional or not, ATP has to go, and needs to be replaced with TCS. To overcome ATP as a barrier to freedom, all citizens should give due consideration to the matter of what True Cycling Support would actually entail.

21 comments:

Very thought provoking...I presumed this idea has been brewing for a long time. I very much like the Dutch cycleways - they work. Any society that provides separate pathways for bike riders, knowingly supports the idea of TCS. Many of the Dutch routes also allow mopeds and motorcycles. And, they obviously put their money where their mouth is - something I can't imagine happening here in this car-centric country.

Thanks for a thoughtful post. I see vehicular cyclists sometimes claiming a lane on Central or other arterial streets where there are no bike lanes. I admire their courage, but can't see that style of riding ever luring less experienced or intrepid riders onto the streets.

Bike lanes on collector streets work well. I feel reasonably safe when pedaling along Maryland Avenue, but even that route benefits from a bike/ped tunnel under SR51 and a bike/ped bridge over I-17. Both are examples of TCS where is most needed in places where bicycles on lightly traveled streets have to cross freeways. My view, then, is that TCS across the board is unlikely, but we should implement it where most needed with more HAWKs, underpasses, buffered bike lanes, and improvements to canal paths.

I'll take a lane on Central coming home from work, but prefer to cut through smaller side streets as the wealthy business men in their Mercedes tend to want to run me down. This takes longer but can be a little less stressful and more enjoyable. One thing that is nice about Central though, is the speed limit is slower and during rush hour the traffic is dense and even slower so cycling pass the cars is rewarding, though it is difficult to merge to make a left.

Pondering your post further, there is more than TCS versus ATP involved. You may expect a follow-up post from me. Though you may enjoy the "walk" post later today which echoes your own theme, though most of it was written before I read this post. Some of it goes to a fundamental difference between our two blogs that might not be noticed by most of our readers.

Steve you tend to side-step my conditional arguments which is totally cool since I am not here to argue much, anyway, and the level of civility and overall coolheadedness on your blog and a handful of others is an atmosphere I strive to maintain. So it is in that spirit that I point out that the basic perspective of the entire post is a conditional: If the goal is to alter the perception of that cycling in America is crazy dangerous, then TCS is the way to go. The "if" part of that conditional is likely not of great interest in the current social/economic/political environment in the U.S. I understand that part. This post is mainly intended to ask questions to those who suggest that ATP is the way to address it, in other words, I do take exception to anyone who suggests that ATP has any change of changing the perception that cycling is dangerous. I don't think it does. In fact, I think it only enhances the perception.

In general, I think the Phoenix Metropolitan area has tremendous bike infrastructure compared to other cities I have lived with the caveat that there are gaps between some of this infrastructure (Specifically more on the fringe - east valley, north phoenix, scottsdale). I think the suburbs have down a pretty good job of instilling TCS, but despite their TCS the masses have not changed their perception that cycling is dangerous.

When I lived in Chandler and rode my bike to Phoenix for work, for the most part I rode on protective bike lanes and canals with lights to cross the street (and I'll tell you that they are really nice!), until you get to downtown (or uptown) Phoenix. This is one of the areas that needs some serious bike infrastructure changes or TCS.

I recently moved to downtown (uptown which is N of the 10) and the thing is although there is pretty much no bike infrastructure on 7th ave to 16th St from I-10 north to Bethany home road; I have noticed I actually see people biking; quite a lot more people than I saw in Chandler where they had very large bike lanes that no one uses. On my 21 mile commute from Chandler I saw maybe 2 other commuters and that was generally closer to Phoenix. Obviously I think some it has to do with class structure as their is a much greater population living on less that are forced to cycle, but I also think there are more people that "get it" and see cycling as sustainable, financially wise, and just plain enjoyable.

I think the perceived notion that cycling is unsafe comes from the fact that masses of drivers are commuters from the burbs and spend most of their time on busy freeways where accidents happen daily as they drive to work to downtown. They exit 7th Street or 7th Ave where the city has some funky rules with the suicide lane turning into a usable lane one way in the evening and the other in morning.

These streets ARE dangerous. The lanes are tiny and compact, and if you don't drive on these streets often people just don't understand the rules. I have to take 7th Ave for a little to get home between Thomas and Indian School and it is one of the scariest bikes rides I do.

Although I don't want to sound to much like a complainypants because I have lived in Dallas where the bike infrastructure is third world compared to Phoenix and the drivers are 10x more aggressive. I think especially around downtown Phoenix and other dense places of "Work" the city needs to improve their TCS. I believe this will have the greatest impact of changing the perception of the masses because right now when drivers see me trying to make a left on 7th ave their perception is it is dangerous, which in that distinct spot I would somewhat agree.

I'm sure everyone knows of a change they would like to make but I'll play a fun game and pretend I am mayor for a day here are a few things I would want to change on my wish list:

1. Reduce 7th ave and 7th st to 2 lanes moving North and South (North lanes is 3 lanes right now) and change the suicide lane to not be used as a usable lane during rush hour. This would allow room to put in bike lanes running both N & S which I think would make a great impression on commuters.

2. Add safety light crossings at canal paths where they intersect major arterial roads in Phoenix (for ex. grand canal & Mcdowell, etc) as these are dangerous to pass and I admit I have misjudged the ATP on these intersections.

financialsalmon (may I call you "financial"?) thank you for your thoughtful comments. The 7s are challenging to ride under the best of circumstances by an experienced cyclist, IMO, I can only imagine what they look like at rush hour to a would-be cyclist: danger zones of imposing magnitude. Even crossing them, at a HAWK, is risky, I was almost taken out by a motorist there who seemed to think the HAWK lights are optional. Phoenix, along with the Valley as a whole, is a good place to ride bicycles, agreed, and this blog is probably an over-enthusiastic statement of that. I would suggest that whatever TCS we have is mainly inadvertent though. The canal banks are usually great places to ride bicycles where they are in a state of good maintenance, and serve as an excellent, and underutilized, resource for two wheeled human powered transport. Euro-style TCS requires several elements that we definitely do not possess currently, however: strict liability for motorists, vulnerable user recognition, and separated facilities for cyclists on routes where auto traffic exceeds about 30 kph, which would be just about every surface street in Phoenix. Oak / Encanto is an excellent cycling route, not because of the zones where there's a bit of paint put down along the side, but because automobile traffic is generally light, slower moving, and in places calmed or diverted. This is inadvertent TCS, not done with any apparent purpose or systematic view of providing a network of cycling routes that serve as a connected system of safe and efficient cycling, but it's a fair glimpse of what would be actually required if we put our minds (and pocketbooks) toward providing subjective safety for cyclists.

Major traffic calming on the 7s would benefit everyone including motorists, although they wouldn't realize that until it was in place. HAWKS at the canal surface crossings would be a doable step towards indicating serious consideration of the importance of nurturing subjective safety to increase cycling numbers. From a systematic perspective, which again is what is needed to nurture cycling across the valley rather than sporadic spot development, the 7th Ave tunnel underpass along the AZ Canal is bizarre, considering that 32nd Street, and Scottsdale Road, and Camelback Road, also cross the AZ Canal, and have zero support for cyclists, pedestrians, or equestrians to cross. Now that last part is not 100% true, as there is a horse crossing button up the street at the Scottsdale/Camelback intersection, with a button high enough for a mounted rider to push. Somehow I don't think that even begins to address the issue of a systematic, consistent provision for subjective safety. I keep watching for a constant stream of equestrians, or cyclists, crossing there, but have yet to see one actually use it.

Yup, I, too, ride the Killing Fields between the east and west boundaries of 44th Street and SR51, and the north and south boundaries of Northern Avenue and the I-10.

I try to never ride ALONG the no-bike-lane-drag-strips like Thomas Road and 44th Street; at least I TRY to never do it for very long. And when I do ride along those streets, it is ALWAYS on the sidewalk (so sue me).

At various points on those Lanes of Death the speed limit is either 35mph or 40mph, which means motorized traffic is ALWAYS moving at between 45mph and 70mph. (Many Arizona drivers apparently believe the "posted speed limit" is the SLOWEST you're supposed to go.) And the laughable concept of "following distance" is unknown to those motorists: you need to "keep up" with the guy in front of you (evidently for "drafting") so a few seconds after 4 PM on a weekday those Highways to Hell look like the first lap of a NASCAR race.

I only CROSS those streets, at an intersection where two of them meet (i.e. 24th Street/Indian School Road and 32nd Street/Thomas Road): stop lights, bus stops, entrances to businesses, pedestrians and even some other brave souls on bicycles are all present there, which tends to slow things down and make it much safer.

If you drive an automobile at the posted speed limit on the streets you mention, other drivers get annoyed as they pass you at 10-20mph higher speed. Following distance must be less than one car length in order to maintain the position and not let The Other Guy cut in front of you, even if you are going 70 mph on a surface street. Heck, especially if you are going 70, since you obviously have Somewhere Important to Be. Crossing the AZ Canal at 44th Street is an interesting cultural exercise. It shows you where we are really at, in 2012, in terms of transportation. What people want is cheaper gas, period, end of transportation planning. I'm just not sure that supply/demand/global politics/economics are in support of that well thought-out plan. Oil prices set to double by 2022, by some accounts. Let's see what 44th Street and the AZ Canal crossing looks like when oil is $226 a barrel.

People don't overestimate the danger of riding a bike. Bikes are dangerous. But people underestimate the danger of driving a car. Cars are dangerous, too—possibly more so than bikes. As it is, an American who drives 15,000 miles per year—that's about average—has a 1% chance of dying in a car crash sometime in their lifetime. That may not sound like much, but it's enough to put cars in the top 10 of leading causes of death in this country.

So as you say, John, getting people out of their cars and onto their bikes isn't so much about the actual safety of biking as it's about its perceived safety. People already willfully engage in dangerous commutes. They just haven't come around to the idea that they can still have their danger while having some fun and saving money, too.

Good points Craig M. Brandenburg. The statistics I've seen put bicycle cycling in the U.S. somewhat more dangerous than driving a car, per mile traveled. I've sometimes wrestled with that denominator, but for a car-free commuter it is relevant since I am just swapping out miles. Overall I believe I was driving three to four times as many total miles per year than I have averaged per year cycling, though, and it's obvious that you can cover more miles in a car per day, up to a factor of ten or so, which would appear to more than counterbalance the risks measured per mile traveled. If someone really wants to review the accident and mortality numbers, they're available online and easily found by the curious, and have been for a long time. Most people I talk with seem so convinced by their own preconceptions of the crazy danger of cycling though that mere numbers wouldn't seem to be able to sway them much. I've tried trotting them out, mainly encountering glazed over eyes in return.

One statistic about cycling that is also important to me, though, is that my chances of killing or seriously injuring another person are exceedingly small while I'm on my bicycle. Not zero, but vanishingly small in comparison to driving a car. I'm plowing a swath of non-killing ability through the public space when I ride. Every cyclist not only lowers the number of cars on the road, but also decreases the overall odds of dying for all other road users. Motorists, I've been making the roads safer for you for the last three years at least.

Danger statistics for cycling are skewed by the inclusion of all sorts of risky behavior performed on bikes: riding against traffic, on sidewalks, on paths that cross driveways, at night witho9ut lights and other correctable errors.

Motorists are often very impatient and feel entitled to all the road they want. A fit, agile cyclist can work around that a lot better than an aging or timid one. Cyclists just starting out, developing their fitness, may be discouraged by honks, yells, close passes and a nagging sense of guilt because they're out there "getting in the way."

Biketopia, or anything approaching it, depends on a complete network of transportation routes, bike-only in some areas and shared with motorists in others. More likely, humans will simply exhaust petroleum without developing a viable alternative and civilization's infrastructure will rapidly degrade under the inexorable reclaiming forces of nature. I hope not, but history shows that we don't really plan ahead very well. Most people are driven by their gut and their gonads.

cafiend thank you for your ideas. TCS seems less like a Biketopian ideal to me since I know that we already spend millions of taxpayer dollars on various bike-related projects every year but with a lack of a coherent TC strategy guiding the expenditures. I see no reason not to send any bike project engineer about to spend taxpayer money to the Netherlands for a tour of the solutions that have been implemented there with great success. The bike project engineer may learn a thing or two that will help to better invest taxpayers' money. We have a bad track record of one-off localized, non-systematic bike projects that literally go nowhere while they use up tax dollars. But if current practice and conditions are any indication, you may turn out to be right about the petroleum exhaustion deal.

I doubt anything like TCS will manifest in this country beyond a few fringe cities that have much higher-than-average bike use. Because in the rest of this country, the public's imagination remains captive to the car as a symbol of freedom and status. The mass of people already choose driving over its alternatives despite the myriad reasons not to drive—cars are expensive; cars make it easy to live unhealthily and acquire preventable diseases; cars are unsustainable and pollute our air; cars cause this country to carry a massive trade deficit every year; cars require oil, which enriches foreigners otherwise not aligned with our interests; cars make killers out of thousands of “innocent” people every year; and so on. I doubt adding to the list another reason not to drive—i.e., bikes are definitely safe—will change people's minds and get them to stop driving. With all the reasons there already are not to drive, and with the continued, habitual use of cars by millions of persons anyway, we can toss out long-term rational self-interest as a motivating methodology for why people transport themselves as they do.

Reforming the way people transport themselves won't be the result of some top-down, well thought-out plan to give people more reasons not to drive their cars. Reform will start by uncontrolled forces recapturing people's imaginations, away from the car and toward something different. Just as the 1969 movie Easy Rider played no small part in an aging Boomer population taking to Harley Davidson motorcycles three decades later in an effort to cling to youth, these kinds of forces that toy with our minds are social, chaotic, and the product of emotions.

Transportation reform will start from the bottom, from individuals choosing one-by-one to abandon the status quo and to do something different with their lives than what their parents did with theirs. And if and when enough people abandon the status quo, eventually our “leaders” will catch on and support us with grand plans for TCS or whatever. But that's far off. Until then, willy nilly bike support is the best possible plan—short of Hollywood making generation-defining movies that celebrate the bike as a symbol of freedom.

Each spurious mile of bike lane we add, though it may go nowhere for you and not help you on your commute, may convince someone elsewhere to drive a little less. That mile of bike lane may be the difference between that person riding to work once or twice a week versus not at all, or riding to the grocery store or library, or to a friend's house on the weekend, or whatever. That isn't the utopia most cyclists want, and it takes waiting a long time for—more than a lifetime, really—but it's a difference we can actually make, now, without requiring massive approval from voters and politicians. And after years of adding lanes and routes and underpasses here and there, ad hoc, a city can end up with a pretty OK bike system—enough to begin changing where people choose to live, where they choose to work, and how they choose to transport themselves.

I make my living by writing software, and so I know a thing or two about complex systems. (That's it, though, just a thing or two.) When I was in my early 20's and fresh out of school, it bugged me that old, well established software systems have so many obvious deficiencies—far-from-optimal designs that are nothing like what a person would come up with if they replaced the system with something new today. This makes mature software systems a lot like road networks, or the health care system, or tax law, or our power grid, or anything big and complex where you look at how it works, scratch your head and say, “Why would anyone design something like that?” The answer is that no one did design it. Instead, it's the result of continual, incremental changes—adaptations and exaptations to handle in real-time ever changing demands on the system.

There's a reason why complex systems have as much elegance as a ball of mud—it's what works. The big, reform-it-all-now plans to fundamentally change the way we do everything usually flop, and meanwhile they do nothing to improve the system we have. I'll take the incremental changes, thank you, because something is better than nothing.

John, I agree with you that bike project engineers ought to tour the Netherlands and other places that have succeeded in creating extensive bike infrastructure that's actually used. It's not so much that such tours would allow our engineers to copy their infrastructures—“Build it, and they will come.” doesn't work in real life, e.g. financialsalmon's comment about all those Chandler bike lanes going unused—but rather such tours would allow our engineers to copy those other cities' engineers' best practices. That's how good engineering works in complex systems.

Craig M. Brandenburg, thanks for the lengthy and thoughtful comment. I would suggest differentiating from full systems which have grown up over time without an overall design or plan, which I also have experienced, and large organizations where standalone Access databases and spreadsheets and other isolated non-systematic islands of data and pseudo-process pop up, and eventually die off. Person in charge of the spreadsheet moves on, it's lost. Reorg the guru who maintained the Access database, and the five users (yes a multi-user Access database, sort of) are left high and dry. Rather than recognize that they have been impacted by poorly thought out support, though, typically they just sour on IT in general. The three rules are: expect that people will actually use it (make it usable), design it to be scalable, and implement it to be sustainable (supportable). Standalone bike lanes fail those rules of good systems, generally. Unused bike lanes are the equivalent of write-only databases.

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Let's Just Ride

I commute by bicycle in Phoenix, Arizona, a metropolis suited to riding bicycles of all types, with weather, mountains, roads, canals, and paths to keep me forever spinning. My favorite bike tools are an open mind, creative engagement, curiosity, compassion, common ground, and the search for knowledge.

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